Inputs

RESULTS

• Frontal Swing (A) (m)  
• Frontal Swing A (FSA): The amount the front corner of a hauling unit swings out relative to the steer path as the combination manoeuvres through a 90 degree turn (12.5-metre radius).
• Frontal Swing (B) (m)  
• Frontal Swing B (FSB): The maximum of the difference between the frontal swing-out distances of adjacent units as the combination manoeuvres through a 90-degree turn (12.5-metre radius). For the purposes of this calculator, FSB is calculated between the hauling unit and the trailing unit behind the hauling unit.
• Frontal Swing (C) (m)  
• Frontal Swing C (FSC): The difference of the maximum between the frontal swing-out distances of adjacent units as the combination manoeuvres through a 90-degree turn (12.5-metre radius). For the purposes of this calculator, FSC is calculated between the hauling unit and the trailing unit behind the hauling unit.
• Low-Speed Swept Path (m)  
• Low-Speed Swept Path (LSSP): The maximum width taken up by the combination as it manoeuvres through a 90-degree turn (12.5-metre radius).
• Tail Swing Requires detailed assessment
• Tail Swing (TS): The maximum amount the rear of the combination ‘swings out’ as it manoeuvres through a 90-degree turn (12.5-metre radius).
• Steer-Tyre Friction Demand Requires detailed assessment
• Steer-Tyre Friction Demand (STFD): The maximum friction demanded by the steer tyres as it rounds a corner manoeuvring through a 90-degree turn (12.5-metre radius). If friction demand is exceeded, the hauling unit will ‘plough straight ahead’.
• Static Rollover Threshold Requires detailed assessment
• Static Rollover Threshold (SRT): The amount of lateral acceleration a vehicle can withstand before rolling over.
• Rearward Amplification Requires detailed assessment
• Rearward Amplification (RA): The amount the trailing units amplify movements induced by the hauling unit during an evasive lane change manoeuvre. Calculated as a ratio between the rearmost roll-coupled unit and the hauling unit.
• High-Speed Transient Off-tracking Requires detailed assessment
• High-Speed Transient Offtracking (HSTO): The distance the rearmost axle of a combination swings outside the path of the steer axle during an evasive lane change manoeuvre.
• Yaw Damping Coefficient Requires detailed assessment
• Yaw Damping Coefficient (YDC): The rate that trailer sway decays after the hauling unit quickly swerves.
• Tracking Ability on a Straight Path Requires detailed assessment
• Tracking Ability on a Straight Path (TASP): The total swept width of a combination when travelling on a straight road with typical road crossfall, road roughness and driver steering.

For more information about the standards see the NHVR website.